Ann Arbor -
For women diagnosed with a type of non-invasive breast cancer, removing the breast is not the only treatment option. Breast conserving surgery, long known to be successful at treating the more common invasive cancer, can also be effective for this pre-invasive condition, according to a new study from researchers at the University of Michigan Comprehensive Cancer Center.

The condition, called ductal carcinoma in situ, or DCIS, is being diagnosed more often. It accounts for 22 percent of all breast cancer diagnoses and affects about 62,000 women each year. If left untreated, DCIS can progress to invasive breast cancer, which is the most common type of breast cancer diagnosed.

Treatment for DCIS is either mastectomy, which removes the entire breast, or breast-conserving lumpectomy, which removes only the cancerous area, followed by radiation therapy.

In this study, researchers at U-M and William Beaumont Hospital in Royal Oak, Mich., looked at the records of women who had opted for lumpectomy and radiation for DCIS between 1981 and 2003. Of the 513 women studied, only 8 percent developed a recurrence of breast cancer or DCIS.

Of those recurrences, 97 percent were detected by mammography, and 91 percent were diagnosed exclusively by mammography, suggesting that regular follow-up mammograms are a reliable way of detecting any return of cancer after breast-conserving surgery.

Renee Pinsky, M.D.

“Lumpectomy with radiation is an excellent treatment for DCIS. Women should not feel they need to have mastectomy in order to have a good prognosis. If they follow up with regular mammograms, a recurrence can be detected early before it has had a negative effect on prognosis,” says study author Renee Pinsky, M.D., assistant professor of radiology at the University of Michigan Medical School. Pinksy presented the findings May 4, 2006, at the American Roentgen Ray Society annual meeting in Vancouver, British Columbia.

The majority of recurrences involved another non-invasive cancer. Among those women who did develop invasive breast cancer, two-thirds had tumors smaller than 1 centimeter, which is considered to be small. All recurrences were stage 0 or 1, the least-advanced and most easily treated stages, which are associated with the best prognosis.